In this paper, we focus on a useful modeling concept that is frequently ignored while formu lating discrete optimization problems. Very often, there exists a natural symmetry inherent in the problem itself that, if propagated to the model, can hopelessly mire a branch-and-bound solver by...

This paper is concerned with the solution of linearly constrained zero-one quadratic programming problems. Problems of this kind arise in numerous economic, location decision, and strategic planning situations, including capital budgeting, facility location, quadratic assignment, media...

This paper deals with the design of dynamic time-space and calibrated static strategic planning models, along with solution algorithms, for the multilevel rail-car fleet management problem faced by RELOAD^®, a branch of the Association of American Railroads (AAR). We discuss a prevalent fleet...

This paper examines the problem of apportioning a railcar fleet to car manufacturers and railroads within a pooling agreement for shipping automobiles. We demonstrate the potential inequities in the presently implemented allocation procedure in the industry, and we propose four alternative...

This paper presents an integer programming model and algorithm for an electric utility capacity expansion problem which considers the option of investing in nondispatchable or renewable energy sources. A branch-and-bound algorithm is proposed for this problem in which the continuous relaxation...